public class Test {
    public static void main1(String[] args) {
        Dog dog = new Dog("wan",11);
        System.out.println("============");
        Cat cat = new Cat();
        System.out.println(cat.age);
        System.out.println(cat.name);
    }


    public static void main2(String[] args) {
        Swap a = new Swap();
        Swap b = new Swap();
        a.val = 10;
        b.val = 20;
        System.out.println(a.val+"  "+b.val);
        exchange(a,b);
        System.out.println(a.val+"  "+b.val);
    }

    public static void exchange(Swap a1,Swap b1){
        int tmp = a1.val;
        a1.val = b1.val;
        b1.val = tmp;

    }


    public static void main3(String[] args) {
        Animal ani = new Animal();
        System.out.println(ani.name);
    }


    public static void main(String[] args) {

    }
}
